// talkback.c 演示与用户交互
#include <stdio.h>
#include <string.h> //提供strlen()函数
#define DENSITY 62.4 //人体密度（单位：磅/立方英尺）

int main(void)
{
    float weight, volume;
    int size, letters;
    char name[40];//name是一个可容纳40个字符的数组
    printf("Hi! What's your first name?\n");
    scanf("%s", name);
    printf("%s, what's your weight in pounds?\n", name);
    scanf("%f", &weight);
    size = sizeof name;
    letters = strlen(name);

    volume = weight / DENSITY;
    printf("Well, %s, your volume is %2.2f cubic feet.\n", name, volume);
    printf("Alse, your first name has %d letters,\n", letters);
    printf("and we have %d bytes to store it.\n", size);

    return 0;
}
    
